// 题目二 练习3
const fp = require('lodash/fp')

//数据
// horsepower 马力，dollar_value 价格， in_stock 库存 
const cars = [
  { name: 'Ferrari FF', horsepower: 660, dollar_value: 700000, in_stock: true },
  { name: 'Spyker C12 Zagato', horsepower: 650, dollar_value: 648000, in_stock: false },
  { name: 'Jaguar XKR-S', horsepower: 550, dollar_value: 132000, in_stock: false },
  { name: 'Audi R8', horsepower: 525, dollar_value: 114200, in_stock: false }, 
  { name: 'Aston Martin One-77', horsepower: 750, dollar_value: 1850000, in_stock: true },
  { name: 'Pagani Huayra', horsepower: 700, dollar_value: 1300000, in_stock: false }
]

// 答案
let _average = function (xs) {
  return fp.reduce(fp.add, 0, xs) / xs.length
}
const values = fp.map(car => car.dollar_value) // fp.map是一个已经柯里化的函数 传入第一个参数 

const f = fp.flowRight(_average, values)
let averageDollarValue = f(cars)
console.log(averageDollarValue)



